Sang Yeong Han, Yoonho Jeong, Hojae Lee, Insung S. Choi
This work presents the metal–organic complex of Fe3+ and benzenehexacarboxylic acid (Fe3+-BHC MOC) as a versatile platform for chemical manipulation and control of interfacial interactions, particularly between living cells and their environment, in the context of single-cell nanoencapsulation (SCNE). Fe3+-BHC MOC forms tunable, hydrophilic films that undergo compositional transformation to Fe3+-phosphate in phosphate-containing media, with distinct kinetics compared with the MOC of Fe3+ and benzene-1,3,5-tricarboxylic acid, which has been employed in the creation of micrometric Transformers. When applied to Saccharomyces cerevisiae, the Fe3+-BHC MOC protocol enables highly cytocompatible SCNE under mild conditions, with controllable shell degradability. The resulting cell-in-shell structures also provide effective cytoprotection against heavy metals and antibacterial agents. The results suggest Fe3+-BHC MOC as a cytocompatible and programmable shell material for constructing artificial spores and expanding the functional scope of MOC-based SCNE platforms.
{"title":"Single-cell nanoencapsulation of Saccharomyces cerevisiae with metal–organic complex nanoshells of Fe3+ and benzenehexacarboxylic acid","authors":"Sang Yeong Han, Yoonho Jeong, Hojae Lee, Insung S. Choi","doi":"10.1002/bkcs.70044","DOIUrl":"https://doi.org/10.1002/bkcs.70044","url":null,"abstract":"<p>This work presents the metal–organic complex of Fe<sup>3+</sup> and benzenehexacarboxylic acid (Fe<sup>3+</sup>-BHC MOC) as a versatile platform for chemical manipulation and control of interfacial interactions, particularly between living cells and their environment, in the context of single-cell nanoencapsulation (SCNE). Fe<sup>3+</sup>-BHC MOC forms tunable, hydrophilic films that undergo compositional transformation to Fe<sup>3+</sup>-phosphate in phosphate-containing media, with distinct kinetics compared with the MOC of Fe<sup>3+</sup> and benzene-1,3,5-tricarboxylic acid, which has been employed in the creation of micrometric Transformers. When applied to <i>Saccharomyces cerevisiae</i>, the Fe<sup>3+</sup>-BHC MOC protocol enables highly cytocompatible SCNE under mild conditions, with controllable shell degradability. The resulting cell-in-shell structures also provide effective cytoprotection against heavy metals and antibacterial agents. The results suggest Fe<sup>3+</sup>-BHC MOC as a cytocompatible and programmable shell material for constructing artificial spores and expanding the functional scope of MOC-based SCNE platforms.</p>","PeriodicalId":54252,"journal":{"name":"Bulletin of the Korean Chemical Society","volume":"46 11","pages":"1088-1092"},"PeriodicalIF":2.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/bkcs.70044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145595269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Landep Ayuningtias, Jae Yeol Ma, Yu-Jin Kim, Yun-Hi Kim
Designing a moderate band gap is sometimes intentionally chosen. When the donor polymer has a deeper HOMO level, a higher Voc can be gained which boosts total PCE in organic photovoltaics (OPVs) (Liao et al., Joule2020, 4(1), 189–206; Mamba et al., J. Phys. Chem. A2021, 125(50), 10593–10603; Choi and Jo, Org. Electron.2013, 14(6), 1621–1628; Jo et al., Org. Electron.2012, 13(10), 2185–2191). This is crucial in DPP-based copolymer frameworks, which frequently have short band gaps and may experience poor Voc. Since DPP is a low bandgap due to strong-acceptor, thus, modifying it with weak donor units can raise the bandgap and lower the HOMO to make it suitable for multi-junctions or higher Voc. We report the synthesis, properties, and photovoltaic applications of a donor-acceptor (D-A) conjugated copolymer based on diketopyrrolopyrrole (DPP) and biphenyl, namely PDDPPhenyl. This polymer exhibits broad absorption ranging from 400 to 900 nm with a band gap of 1.59 eV. As expected, a low HOMO level of −5.29 was gained by introducing biphenyl as a weaker donor. The optimized weight ratio goes to 1:4 for PDPPPhenyl:PC71BM with 3.8% PCE.
{"title":"Synthesis and characterization of diketopyrrolopyrrole-based conjugated polymer with biphenyl for organic photovoltaic cells","authors":"Landep Ayuningtias, Jae Yeol Ma, Yu-Jin Kim, Yun-Hi Kim","doi":"10.1002/bkcs.70042","DOIUrl":"https://doi.org/10.1002/bkcs.70042","url":null,"abstract":"<p>Designing a moderate band gap is sometimes intentionally chosen. When the donor polymer has a deeper HOMO level, a higher Voc can be gained which boosts total PCE in organic photovoltaics (OPVs) (Liao et al., <i>Joule</i> <b>2020</b>, <i>4</i>(1), 189–206; Mamba et al., <i>J. Phys. Chem. A</i> <b>2021</b>, <i>125</i>(50), 10593–10603; Choi and Jo, <i>Org. Electron.</i> <b>2013</b>, <i>14</i>(6), 1621–1628; Jo et al., <i>Org. Electron.</i> <b>2012</b>, <i>13</i>(10), 2185–2191). This is crucial in DPP-based copolymer frameworks, which frequently have short band gaps and may experience poor Voc. Since DPP is a low bandgap due to strong-acceptor, thus, modifying it with weak donor units can raise the bandgap and lower the HOMO to make it suitable for multi-junctions or higher Voc. We report the synthesis, properties, and photovoltaic applications of a donor-acceptor (D-A) conjugated copolymer based on diketopyrrolopyrrole (DPP) and biphenyl, namely PDDPPhenyl. This polymer exhibits broad absorption ranging from 400 to 900 nm with a band gap of 1.59 eV. As expected, a low HOMO level of −5.29 was gained by introducing biphenyl as a weaker donor. The optimized weight ratio goes to 1:4 for PDPPPhenyl:PC<sub>71</sub>BM with 3.8% PCE.</p>","PeriodicalId":54252,"journal":{"name":"Bulletin of the Korean Chemical Society","volume":"46 7","pages":"754-760"},"PeriodicalIF":1.7,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nonvide Nicolas Adiko, Hyeon Tae Seo, Dae-Won Ki, Jung Hee Park, Da Som Kim
Ornithine decarboxylase (ODC) is a critical enzyme in the polyamine biosynthesis pathway that catalyzes the conversion of l-ornithine to putrescine using pyridoxal 5′-phosphate (PLP). Lactobacilli act probiotically by stimulating the immune system, defending against pathogens, and mitigating the impact of various chronic illnesses. To better understand the function and structure of ODC from Lacticaseibacillus rhamnosus (LrODC-WT), we investigated its enzymatic activity, kinetic characteristics, crystal structure, and further examined a variety of single-residue mutants. We found that active LrODC-WT has the following kinetic parameters: KM 6.83 ± 1.01 mM, kcat 1.44 ± 0.1 s−1, and kcat/KM 210.83 ± 19.37 M−1 s−1. Unlike LrODC-WT, H346A, F186A, H216F, and E281Q showed no catalytic activity. H346A showed maximum unfolding at 2 M guanidine hydrochloride (GdnHCl), while the other enzymes exhibited peak unfolding effects at 1 M, indicating that H346A shows higher resistance to GdnHCl. The PLP binding in LrODCs using a UV/Vis spectrometer showed that LrODC-WT possesses high PLP, while F186A and H346A demonstrated 50% PLP of LrODC-WT, and absent in H216F and E281Q. The crystal structure of LrODC-WT was identified as a tetramer in which PLP was bound to all four subunits and interacted with residue K347 for Schiff base formation. While the crystal structures of H216F and H346A form dimers, an LrODC-WT tetramer can form via hydrogen bonding of D544 and N270. An improved understanding of the structure and function of LrODCs is relevant for controlling its polyamine production and for optimizing L. rhamnosus strains for use as a more potent probiotic.
{"title":"Insight into the functional and structural relationship of ornithine decarboxylase and its mutants from Lacticaseibacillus rhamnosus","authors":"Nonvide Nicolas Adiko, Hyeon Tae Seo, Dae-Won Ki, Jung Hee Park, Da Som Kim","doi":"10.1002/bkcs.70035","DOIUrl":"https://doi.org/10.1002/bkcs.70035","url":null,"abstract":"<p>Ornithine decarboxylase (ODC) is a critical enzyme in the polyamine biosynthesis pathway that catalyzes the conversion of <span>l</span>-ornithine to putrescine using pyridoxal 5′-phosphate (PLP). Lactobacilli act probiotically by stimulating the immune system, defending against pathogens, and mitigating the impact of various chronic illnesses. To better understand the function and structure of ODC from <i>Lacticaseibacillus rhamnosus</i> (LrODC-WT), we investigated its enzymatic activity, kinetic characteristics, crystal structure, and further examined a variety of single-residue mutants. We found that active LrODC-WT has the following kinetic parameters: <i>K</i><sub>M</sub> 6.83 ± 1.01 mM, <i>k</i><sub>cat</sub> 1.44 ± 0.1 s<sup>−1</sup>, and <i>k</i><sub>cat</sub>/<i>K</i><sub>M</sub> 210.83 ± 19.37 M<sup>−1</sup> s<sup>−1</sup>. Unlike LrODC-WT, H346A, F186A, H216F, and E281Q showed no catalytic activity. H346A showed maximum unfolding at 2 M guanidine hydrochloride (GdnHCl), while the other enzymes exhibited peak unfolding effects at 1 M, indicating that H346A shows higher resistance to GdnHCl. The PLP binding in LrODCs using a UV/Vis spectrometer showed that LrODC-WT possesses high PLP, while F186A and H346A demonstrated 50% PLP of LrODC-WT, and absent in H216F and E281Q. The crystal structure of LrODC-WT was identified as a tetramer in which PLP was bound to all four subunits and interacted with residue K347 for Schiff base formation. While the crystal structures of H216F and H346A form dimers, an LrODC-WT tetramer can form via hydrogen bonding of D544 and N270. An improved understanding of the structure and function of LrODCs is relevant for controlling its polyamine production and for optimizing <i>L. rhamnosus</i> strains for use as a more potent probiotic.</p>","PeriodicalId":54252,"journal":{"name":"Bulletin of the Korean Chemical Society","volume":"46 7","pages":"730-742"},"PeriodicalIF":1.7,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/bkcs.70035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The cover image depicts a Goldberg machine symbolizing the stereodivergent reaction of α-azaaryl carbonyl derivatives with electrophilic partners (E⁺), producing azaarenes with multiple stereocenters (R,S). By combining a chiral copper Lewis acid with a second chiral catalyst (Ir, Pd, Ni, Ru, or amines) and tuning the stereochemical environment, all possible stereoisomers can be selectively accessed. Details are in the article by Ilwoo Song, Byungjun Kim, Hooseung Lee, and Sarah Yunmi Lee.